Using up and down of ocean waves to generate power, is a newly researched energy, which is not only environment friendly but also always available for use. Presently, there have been many designs and plans using ocean waves to generate power, such as Chinese Patent Application with Publication No. CN1080692A, disclosing a wave power generating device, providing a stay rod attached to a concrete anchor block sinking to the seabed (epicontinental sea), or installing the stay rod on a stable plate kept in a certain depth under water (deep sea place), wherein the stay rod passes through a hole of a floating plate, thus the toothed rack (or frictional strip) on the stay rod is engaged (or contacted ) with the input gear (or friction gear) of the rotating transmission device on the floating plate where the rotating transmission device converts a bidirectional movement to an unidirectional movement; up-and-down movements of the ocean waves make the floating plate reciprocating along the stay rod, in such way, converting the reciprocating motion of the toothed rack into rotation motion of the gear, which is then converted into a unidirectional rotation motion utilized to drive a generator to generate power. This wave power generating device has complex structure, big loss, low efficiency, and not available for multiple uses.